Question

I need to change the DataTemplate for items in a ListBox depending on whether the item is selected or not (displaying different/more information when selected).

I don’t get a GotFocus/LostFocus event on the top-most element in the DataTemplate (a StackPanel) when clicking the ListBox item in question (only through tabbing), and I’m out of ideas.

Answer 1

The easiest way to do this is to supply a template for the ‘ItemContainerStyle’ and NOT the ‘ItemTemplate’ property. In the code below I create 2 data templates: one for the ‘unselected’ and one for the ‘selected’ states. I then create a template for the ‘ItemContainerStyle’ which is the actual ‘ListBoxItem’ that contains the item. I set the default ‘ContentTemplate’ to the ‘Unselected’ state, and then supply a trigger that swaps out the template when the ‘IsSelected’ property is true. (Note: I am setting the ‘ItemsSource’ property in the code behind to a list of strings for simplicity)

<Window.Resources>  <DataTemplate x:Key='ItemTemplate'>     <TextBlock Text='{Binding}' Foreground='Red' /> </DataTemplate>  <DataTemplate x:Key='SelectedTemplate'>     <TextBlock Text='{Binding}' Foreground='White' /> </DataTemplate>  <Style TargetType='{x:Type ListBoxItem}' x:Key='ContainerStyle'>     <Setter Property='ContentTemplate' Value='{StaticResource ItemTemplate}' />     <Style.Triggers>         <Trigger Property='IsSelected' Value='True'>             <Setter Property='ContentTemplate' Value='{StaticResource SelectedTemplate}' />         </Trigger>     </Style.Triggers> </Style>  </Window.Resources> <ListBox x:Name='lstItems' ItemContainerStyle='{StaticResource ContainerStyle}' />